Linearly-rising part of the oxidatively-heating process

The time, A t, required for the temperature of 2 cm of the substance charged in the draft cell, into which air is supplied, and subjected to the adiabatic oxidatively-heating test started from a below about 180 °C to increase by the definite value of AToi 1.25 K from the corresponding standard temperature is determined on the linearly-rising part of the oxidatively-heating process or curve of the substance. 

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